May 11, 2010
09:00 AM (EDT)

News Release Number: STScI-2010-14

Hubble Catches Heavyweight Runaway Star Speeding from 30 Doradus

May 11, 2010: A blue-hot star, 90 times more massive than our Sun, is hurtling across space
fast enough to make a round trip from Earth to the Moon in merely two hours.
Though the speed is not a record-breaker, it is unique to find a homeless star
that has traveled so far from its nest. The only way the star could have been ejected from the star cluster where it was born is through a tussle with a rogue star that entered the binary system where the star lived, which ejected the star through a dynamical game of stellar pinball. This is strong circumstantial evidence for
stars as massive as 150 times our Sun's mass living in the cluster. Only a very
massive star would have the gravitational energy to eject something weighing
90 solar masses. The runaway star is on the outskirts of the 30 Doradus nebula,
a raucous stellar breeding ground in the nearby Large Magellanic Cloud. The
finding bolsters evidence that the most massive stars in the local universe reside
in 30 Doradus, making it a unique laboratory for studying heavyweight stars. 30
Doradus, also called the Tarantula Nebula, is roughly 170,000 light-years from
Earth.